Objectives: Evidence from the US Truth® campaign suggests that interventions focusing on tobacco industry practices and ethics may be effective in preventing youth smoking uptake. We developed, piloted and evaluated a school-based intervention based on this premise.Methods: Exploratory study Students in Years 7–8 (aged 11–13) in two UK schools received Operation Smoke Storm, comprising three 50-minute classroom-based sessions in Year 7, an accompanying family booklet and a 1-hour classroom-based booster session in Year 8. We compared the risk and odds of ever smoking and susceptibility to smoking in Year 8 students in study schools post-intervention compared with students in control schools. Focus groups and interviews with students, teache...